The present invention generally relates to a fire prevention sleeve.
Such fire prevention sleeves are known in several different embodiments. In case of fire they serve to seal penetrations in walls, ceilings, or floors of buildings, through which inflammable or melting pipelines are guided. For this purpose, the fire prevention sleeve is arranged around the pipes such that in case of a fire the then expanding fire prevention insert seals the penetration as tightly as possible. Here, the fire prevention sleeve is usually arranged at the outside of the opening, thus for example at the wall with the penetration extending through it. Common sheet metal may be used as the jacket for the strip of intumescent material. With such a jacket any expansion pressure of the fire prevention insert generated in case of fire may be well supported so that it is ensured that the fire prevention insert is expanded in a targeted fashion in the direction the opening shall be sealed.
In the constructions of prior art it is disadvantageous that the fire prevention insert is embodied as a thin strip of few millimeters, which fails to completely fill the space defined by the jacket so that in case of a given circumference of the sleeve no flexibility is provided with regards to the circumference of the pipelines to be enclosed. Such a certain type of sleeve is only suitable for a certain pipeline diameter and, when the diameter of the pipe to be enclosed is smaller than predetermined by the sleeve, the annular gap between the pipe and the penetration cannot be sealed in a smoke and gas-tight fashion.
In particular, in case of the use of the known fire prevention sleeves for lines, cables, and the like, any retrofitting of additional lines or cables would only be possible by an exchange of already assembled sleeves occurred with sleeves showing a greater diameter. Additionally, the sleeve itself, usually comprising a sheet metal, limits the minimum circumference of the line(s) and cable(s) to be sealed, thus circumferences of arbitrarily small diameters cannot be encased by the sleeve. Accordingly, this fire prevention sleeve cannot be used for sealing individual lines or cables with relatively small diameters.
Due to the fact that the fire prevention insert of fire prevention sleeves of prior art usually show very little compressive features, cable strands comprising several cables, for example, cannot be sealed in a smoke gas-sealed fashion, because the gore between the individual lines cannot be sealed by the fire prevention insert. For this purpose, additional measures are required, such as an additional seal of the passage through the construction part, for example with fire prevention foam, a fire prevention material, or the like.
Further, the fire prevention sleeves of prior art fail to allow any smoke gas sealing in case of cables laid in a very unstructured fashion because they show little flexibility and are designed for the sealing of pipes and line strands as circular as possible.
In practice, cable strands are usually sealed by intumescent sealants, such as fire prevention foam, fire prevention mortar, or similar sealing materials, with the gap between the cable strand and the construction part being filled with the intumescent sealant. Here, it is not reliably ensured that the installation specifications according to the licenses of the fire prevention products are complied with, such as maximum number of cables laid, installation depth, maximum cross-section of the opening, and wall distances. Furthermore, the lasting sealing of cable conduits is very time-consuming.